In article , tony sayer

wrote:
In article
s.com, Andre Jute scribeth thus


Mmm. I too have a 405 which has given sterling service. If it is so
efficient, I wonder why Peter Walker, not notably a waster, included
that large, expensive heatsink at the back.

Prolly as their products went world-wide aimed for hotter climes?..

I suspect he may have had IHFA707 in mind... ;-

That was the test which came into use to try and deal with makers inventing
bloated power ratings. The snag was that it defined that any test had to be
done with the amp 'pre conditioned' by being run at 1/3rd the rated power
for an hour before the power was checked at the rated amount.

Useful as a test for weeding out amps with bogus power claims, but had
little to do with use for most music which - in those days at least - had
crest factors well over 10 in most cases. Although I have my doubts how
common that is nowdays.

Slainte,

Jim

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